Isuzu Trooper Shifts hard and Engine Revving in stop?

Inspect the throttle body and idle air control valve closely.It also sounds like carbon is sticking the throttle control open on this car.
While the engine is revving high remove the throttle cable at the throttle shaft. If the RPM does not return to an idle, remove the air intake hose [in front of the throttle plate] Check that the butterfly is all the way closed. If so then replace the TPS.
In some cases cable gets stuck up.
In throttle body area there are two lines one for the actually gas pedal and the other for the cruise control. What happens is the cable gets stuck, causing the engine to rev high, normally if you just drive around the cable goes back down.If all this checked ok and there is power brake system on your car then its Vacuum leak.
Vacuum leak sounds right. It might be inside the booster. Try plugging the line to the booster to see if it idles better. Or listen carefully under the dash for a hiss when you push on the brake.
The booster is on the firewall in front of the driver. In other words, it is to the back right of the engine compartment as you look under the hood.If all checked ok,then it can be Faulty brake booster causing the fault.

See how the brake booster looks.

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This details will help you.

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If you need dis-assembly or replacement instructions for any other auto/car part, or you want to ask question related to your car/truck jeep problem then please leave the comment with your details, so I can provide you the required instructions and solutions.

For more brake related help solutions,see the list below :----

Brake System Troubleshooting?

http://technoanswers.blogspot.com/2011/11/brake-system-troubleshooting.html

How Anti-Lock Brakes Work?

http://technoanswers.blogspot.com/2011/11/how-anti-lock-brakes-work.html

Car Brake lines have no pressure?

http://schematicsdiagram.blogspot.com/2011/12/car-brake-lines-have-no-pressure.html

Where is Power Brake Booster located on 1995 Lincoln Town Car?

http://howtobyme.blogspot.com/2011/12/where-is-power-brake-booster-located-on.html

How to Replace Power Brake Booster on 1996 GMC Jimmy?

http://schematicsdiagram.blogspot.com/2011/12/how-to-replace-power-brake-booster-on.html

Abs and service light comes on?

All types of brake problems and repairs

http://howtobyme.blogspot.com/2011/11/abs-and-service-light-comes-on.html

ABS light stays on but brakes work fine?

http://howtobyme.blogspot.com/2011/11/abs-light-stays-on-but-brakes-work-fine.html

VCS maintenance required on Toyota Camry?

http://howtobyme.blogspot.com/2011/11/vcs-maintaince-required-on-toyota-camry.html

VCS and ABS lights go on and off intermittently on Lexus?

http://howtobyme.blogspot.com/2011/11/vcs-and-abs-lights-go-on-and-off.html

ABS & Brake lights warning indicator steady on dash and speedometer not working for Dodge Ram?

http://howtobyme.blogspot.com/2011/11/abs-brake-lights-warning-indicator.html

E-brake is stuck down on Ford Focus?

http://schematicsdiagram.blogspot.com/2011/12/e-brake-is-stuck-down-on-ford-focus.html

When the car stops, abs pump turns ON?

http://howtobyme.blogspot.com/2011/12/when-car-stopsabs-pump-turns-on.html

Sometimes ABS light comes on while Driving?

http://howtobyme.blogspot.com/2011/12/sometimes-abs-light-comes-on-while.html

How to Disconnect Power to EBCM on Pontiac Grand Prix?

http://schematicsdiagram.blogspot.com/2011/12/how-to-disconnect-power-to-ebcm-on.html

Where is ABS/TCS module located on 2005 Cadillac Deville

http://schematicsdiagram.blogspot.com/2011/12/where-is-abstcs-module-located-on-2005.html

Car shudders and dies?

In most of cases this is caused by dirt throttle plate.Carbon build up on throttle plate.Get the throttle body cleaned completely,with throttle clearer, which you can get from local auto parts store.But if that is not helping,then I believe your concern is the transaxle. I believe your losing line pressure from internal leaks in the transaxle and this is causing the converter clutch to engage. You need to have the line pressure monitored as well as the converter clutch using a pressure gauge and scan tool.Either get this test done at professional auto garage or at dealership or get this tools from local auto parts store, to perform the test yourself.At auto parts store, they provide the pressure gauge tool and scan tool for rent and when you return the tools back, they deduct there minimum fees and return you the remaining amount.

This details will help you to test and confirm the problem.

Truck will not start due to sitting long for years?

Most possibly,this is case of Truck not been driven for years.The injectors gets clogged/ blocked.Check the injector movements while you start /turn the key to start.
Possible injectors are gummed up. Try putting 5 gallons high octane fuel and a concentrated amount of injector cleaner, Try a spray starting fluid, and spray into throttle body while some one cranks over.

This details will help.

For more car related problem troubleshooting:---

This are the sections, you can go through and click the link to read its troubleshooting.

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The car will not start?

http://schematicsdiagram.blogspot.com/2011/06/car-will-not-start.html

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Car will not crank?

http://schematicsdiagram.blogspot.com/2011/06/car-will-not-crank.html

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Car has no spark?

http://schematicsdiagram.blogspot.com/2011/06/car-has-no-spark.html

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How to troubleshoot car battery?

http://schematicsdiagram.blogspot.com/2011/06/how-to-troubleshoot-car-battery.html

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How to test starter solenoid?

http://schematicsdiagram.blogspot.com/2011/06/how-to-test-starter-solenoid.html

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How to test cars starter?

http://schematicsdiagram.blogspot.com/2011/06/how-to-test-cars-starter.html

How to replace starter in car?

http://schematicsdiagram.blogspot.com/2011/06/how-to-replace-starter-in-car.html

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car will turn over but will not start?

http://technoanswers.blogspot.com/2011/05/car-will-turn-over-but-will-not-start.html

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Car wont start?

http://howtobyme.blogspot.com/2011/10/car-wont-start.html

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